Police have not yet released the name of the suspect involved in the rampage, which left at least seven others injured.

But Santa Barbara County sheriff Bill Brown said investigators were familiar with a video posted to YouTube entitled, "Elliot Rodger's Retribution," in which a man rants against women that have allegedly rebuffed his advances.

"We have obtained and are currently analyzing both written and videotaped evidence that suggests this atrocity was a premeditated mass murder," Brown said in an early-morning press conference. He said the videotaped and written evidence "appear to have been completed by the suspect."

When asked if that evidence included the "Elliot Rodger's Retribution" video, Brown said, "We're investigating to determine that at this time. But it would appear that that is connected with this crime."

At the beginning of the video posted to YouTube, the man says that it will be his last one. He goes on to promise "retribution" to unspecified women.

"Girls gave their affection and sex and love to other men but never to me," the man says, adding that he's been "forced to endure an existence of loneliness, rejection, and unfulfilled desires all because girls have never been attracted to me."

The man also calls himself the "supreme gentleman," while referring to other men as "obnoxious brutes."

"College is the time when everyone experiences those things such as sex and fun and pleasure. But in those years I've had to rot in loneliness. It's not fair. You girls have never been attracted to me. I don't know why you girls aren't attracted to me. But I will punish you all for it," he says.

"All those girls that I've desired so much, they would've all rejected me and looked down on me as an inferior man if I ever made a sexual advance towards them."

The video runs for almost seven minutes. Near its end, he promises a day of "revenge."

"Tomorrow is the day of retribution," the man says. "The day in which I will have my revenge against humanity."

Brown said in his press conference that the violence comprised about a 10-minute span, from the first emergency call at 9:27 p.m. PT to the discovery of the dead gunman.